Sense amplifiers are used to detect differences between two voltages. Sense amplifiers typically are used, for example, to read the contents of memory cells in memory arrays. A memory cell whose contents are to be read are coupled to a sense amplifier via two bit lines. The sense amplifier detects the relative voltages on the two bit lines and, in response to those voltages, provides an output signal representative of a data value stored within the memory cell.
Conventional sense amplifiers are most sensitive to voltages around half of the source voltage (e.g., V.sub.dd /2). However, this voltage typically is not available in the circuit and thus must be generated by additional circuitry. Conventional sense amplifiers include one or more additional stages, following the sensing stage, to restore output voltages to CMOS logic levels. These additional stages increase manufacturing costs, reduce operating speed, and require additional wafer space. Furthermore, conventional sense amplifiers draw current from supply lines (e.g., V.sub.dd), and thus consume power even when the sense amplifier is not reading data from a memory cell.